It depends on your genetics. Most likely between ages 30-50.
when you start puberty
Depends on your genes
no the die just wares off
Going to a different country will not necessarily make your hair turn gray. How early someone may get gray hair is determined by our genes. Most people get gray hairs around the same age their grandparents got gray hairs. In addition, stress can damage the melanin, which gives the growing shaft of hair it's color.
Some have gray hairs as young as the age of 12, so for people, there hasn't been a set age on getting them.
Yes, with the advancement in age the color of hairs turn gray. The change in color from black to gray in hairs is a natural process provided you do not resort to artificial coloring of hairs.
Use color or natural Treatment
Growing armpit hair is a sign you have already started puberty.
No, nose hairs start growing at the top of the nose and work it's way down. When you pluck nose hair you only take out 1/3 of the actual length.
getting older
Nothing happens when you pluck a gray hair
There are 100,000 hairs growing every second. Not very fast, but they're growing!